spatio-temporal variations in demersal fish community along

Spatio-temporal variations in demersal fish community along the fishing grounds

of Goa West coast of Indiaof Goa, West coast of India

C U Rivonker1 V P Padate1 S S Sawant2 K Venkat2C.U.Rivonker , V.P.Padate , S.S.Sawant , K.Venkatand A.C.Anil2

1 D t t f M i S i G U i it T l i Pl t 1 Department of Marine Sciences, Goa University, Taleigao Plateau, 403 206, Goa.

2 National Institute of Oceanography Dona Paula 403 004 Goa2 National Institute of Oceanography, Dona Paula, 403 004, Goa.

Feb, 2006 – May, 2007Feb, 2006 May, 200748 trawl hauls40 offshore (1 3 hrs)40 offshore (1- 3 hrs)08 inshore (1 hr)Random samplingBeach seines (02)( )

Red-belly yellow tail fusilier - Caesio cuning (Bloch, 1791)(Actinopterygii: Perciformes: Caesionidae)( p yg )

ReefReef--inhabitant and midinhabitant and mid--water schooling species (Fishbase, 2007).water schooling species (Fishbase, 2007).

Earlier reports Earlier reports –– Sri Lanka to Vanuatu and from Southern Japan to Sri Lanka to Vanuatu and from Southern Japan to Australia and Port Blair Australia and Port Blair –– Indian coast (Fishbase, 2007).Indian coast (Fishbase, 2007).

“Fi t d t id th i l k hi l “Fi t d t id th i l k hi l “First record outside the previously known geographical “First record outside the previously known geographical

– 137 (91 / 46)137 (91 / 46).– Marine Estuarine Opportunists.

P blished Literat re (Ansari et al 1995 2003)– Published Literature (Ansari et al., 1995; 2003)– Present study

– Wide habitats– Rare speciesp

BeachEstuary

OceanOcean

g pg p

– A contrastA contrastPost-larvae

Burrowing gspecies

GOAAdult prawns

Adults

Juveniles

Wandering species

Karwar

Juveniles

p pst liferastyliferaMarine, stenohaline.

Spawning - deeper watersSpawning - deeper waters

monsoon and post-monsoon seasons.

Metapenaeus dobsoniEuryhaline.

Recruitment - pre-monsoon.

y

Perennial breeder.

Metapenaeus affinisMinor contributionMinor contribution.

Spawning - post-monsoon.

Recruitment - pre-monsoon.p

GOA

Metapenaeus dobsoni

O2-deficient bottom waters

(A O t)(Aug-Oct)

Sub-surface hypoxia

(< 0 5 ml l-1 )

Invasion?

(< 0.5 ml.l-1 )

Denitrification and sulphate

reductionWater Quality

Migration

Fishing Migration

to estuarypressure

Anthropogenic t opoge c

input

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